How to modify js file on client side?

I would like to edit part of the .js file. I mean add some code, and these code should be executed when I open the website (in browser开发者_运维知识库). How I can do that?

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The easiest way to do that is to use jquery and put your code into

$(document).ready(function() {
 //your code
}

or if you don't want to use jQuery

document.onload = function()
{
//your code here

}

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If you want to add on to existing JavaScript code for a site, I am not sure that you can in a permanent way. However, if you want to change some sort of behaviour just for you, you could take a look into creating a userscript. There are many examples at userscripts.org.

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You cannot edit the js file but you can override the functions and the variables. This will work unless the js file is not protected by closure.

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You can't modify the js file on client side. However, if you just want to add some code, you can use userscript.

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this is a bad...

but if the js is not remote, use AJAX to read the file contents, then change what you need then use the DOM to create the script tag and use .innerHTML to put the content in.

if you would like code tell me if you want JQuery or native and i will post

P.S if the file is remote there is no way to do it...